温度和光周期对苦瓜性别表现的影响

苦瓜苗期所处的环境条件会影响其性别表现，株洲长白和英引苦瓜品种的光周期反应表现为短日效应，即短日使植株的发育提早，并促进雌性发育，长日的效果恰好相反。苦瓜苗期短日处理时期以出苗至６片真叶（苗龄２０天）为宜。低温可以增强短日效应，高温则使苦瓜的生殖生长推迟，并削弱短日效应，短日低温是苦瓜苗期最适宜的环境条件。     

短日照处理天数对一品红开花和观赏品质的影响

 短日照处理不同天数后转到自然长日照下, 研究短日照处理对促成栽培的‘千禧’和‘早生天鹅绒’一品红生长开花的影响。结果表明短日照处理天数对其发育进程、苞片着色和观赏品质有显著影响。苞片转色后结束短日照处理, 节数与连续短日照相似, 但开花显著延迟; 现蕾时结束短日照处理, 开花时间、冠幅与连续短日照相似; 过渡性叶片面积在短日照处理至现蕾后13～14 d才与连续短日照相似。一品红对短日照处理天数的反应存在品种差异。现蕾前结束短日照处理导致一品红过渡性叶片的节间和花梗伸长、苞片着色变差, 出现开花逆转现象。为了保证观赏品质, 短日照处理要持续到现蕾以后。     

Flower formation of Chinese cabbage. II. Anti-vernalization and short-day treatment

The influence of high temperature (anti-vernalization) and short-day treatment during the raising of transplants on the bolting of Chinese cabbage having early planting-dates has been tested. A temperature rise from 18 to 26°C resulted in a delay in bolting, but only caused a slight increase in leaf number. Hence, Chinese cabbage shows anti-vernalization effects. The raising of transplants below 20°C and with short-day treatment for energy saving cannot be recommended, since the effect of the short-day treatment is too small.     

A method to calculate the number of wheat seedlings in the 1st to the 3rd leaf growth stages

Background

The number of cultivated wheat seedlings per unit area allows calculation of plant density. Wheat seedling density provides emergence data and this is useful for improving crop management. The number of wheat seedlings is typically determined by visual counts but this is time-consuming and laborious.

Results

We obtained field digital images of 1st to 3rd leaf stage wheat seedlings. The seedlings were extracted using an image analysis technique that calculated the coverage degree of the seedlings and the number of angular points of overlapping leaves. The wheat seedling quantity estimation model was constructed using multivariate regression analysis. The model parameters included coverage degree, number of angular points, variety coefficient, and leaf age. Introduction of the number of angular points increased the accuracy of the single coverage degree model. The R² value was consistently?>?0.95 when the model was applied to different varieties, indicating that the model was adaptable for different varieties. As the leaf stage or density increased, the accuracy of the model declined, but the minimum R² remained?>?0.87, indicating good adaptability of the model to seedlings with different leaf ages and densities.

Conclusions

This method is an effective means for counting wheat seedlings in the 1st to the 3rd leaf stages.

     

柚杂交一年生苗性状分离初步研究

对5个杂交组合120株柚品种间杂交1年生苗树体和叶片性状进行了调查、分析。结果表明，柚杂种1年生苗的同一组合的不同单株间性状即出现分离，特别是株高、叶片数、总叶面积和分枝数等性状分离现象最为明显，可作为杂种实生苗早期鉴定、选择的重要指标；柚不同组合间苗期多数性状表现出有显著差异，母本对杂种1年生苗性状表现影响最为明显；被测性状的株间变异大于组合间变异，相同组合不同单株选择不容忽视。     

Effect of plant age and temperature on bolting in Chinese cabbage

The antioxidant BHT — commonly used as a food stabilizer — when applied in aqueous solution to the tips of 5-day-old pea seedlings, to young apple seedlings or to germinating lettuce seeds, produced a suden cessation of growth that, when growth was resumed, was followed by certain morphological changes. Treatments with BHT caused the formation of (1) a bunch of new shoots arising at the apex of apple seedlings, (2) 2 or 3 adventitious fast-growing shoots from the base of the pea hypocotyl, and (3) adventitious growing points in lettuce plants. This multiplication of growing points was followed, during further development, by splitting of the apple seedling stems and lettuce leaf blades into independently growing organs.     

不同光照条件对一串红“猩红皇后”幼苗生长的影响

通过搭建黑色网纱对一串红新品种"猩红皇后"的幼苗进行了不同光照强度的试验。结果表明:不同光照条件对一串红幼苗的株高、地径、叶量、叶面积、茎叶及根系的鲜干重有不同影响,遮光率为60%左右有利于幼苗的株高、地径、叶片数、叶面积的增长,也有利于根系的生长;遮光率为90%以上对幼苗生长有负作用;不同遮光处理对幼苗生长的影响发生明显变化在1周以后,18 d后60%遮光处理组与70%相比生长优势明显。     

不同氮素形态配比对猴樟幼苗生长发育的影响

以1年生猴樟幼苗为试材,按NH^+_4-N∶NO^-_3-N体积比为0∶10、3∶7、5∶5、7∶3、10∶0配制营养液处理,42 d后,检测其幼苗株高、茎粗、总叶片数量、茎叶干质量、叶绿素含量、根系活力、新根数量、根干质量、根冠比,研究了不同氮素形态对猴樟幼苗生长发育的影响,以期为猴樟在盐碱地区进行引种推广和栽培提供技术支撑。结果表明:NO^-_3-N∶NH^+_4-N为5∶5处理对猴樟生长发育最适合。NH^+_4-N∶NO^-_3-N为5∶5处理条件下猴樟幼苗茎叶和根系生长量最大,根系活力和叶绿素含量最高,而在NH^+_4-N∶NO^-_3-N为3∶7和7∶3处理条件下,猴樟幼苗茎叶和根系生长量变小,根系活力和叶绿素含量变低,完全无NH^+_4-N或完全无NO^-_3-N条件下,猴樟幼苗叶片小、茎干细弱、根系少、根系活力低。     

硫酸铜乳胶漆制剂对银荆容器播种苗生长的影响

研究了不同质量分数CuSO4乳胶漆制剂处理容器内壁对银荆播种苗生长的影响。结果表明:不同浓度CuSO4乳胶漆制剂对银荆播种苗主根生长具有抑制作用,浓度为270g/LCuSO4处理后的银荆播种苗主根最短(1.125cm),对照组最长(9.5cm);不同浓度CuSO4乳胶漆制剂对容器苗侧根数量、复叶数量、小叶数量、叶面积、茎重、根重及苗高增加均具有显著的促进作用;190g/L CuSO4乳胶漆制剂处理容器内壁能显著抑制银荆1a生播种苗主根生长,提高苗木质量。     

干旱胁迫对杏脂氧合酶活性的影响

为了研究脂氧合酶(LOX)在植物干旱反应中的作用,以抗旱的山杏和抗旱性弱的龙王帽实生苗为试材,观察了自然干旱过程中叶片的生长状况以及测定了土壤含水量、新叶生长率、叶片脱落率、根和叶片的LOX活性。结果表明,在自然干旱过程中随着土壤含水量的降低,山杏和龙王帽的新叶增长率也下降。干旱后期山杏比龙王帽的新叶增长速率下降快、生长停止早。干旱使山杏比龙王帽叶片早脱落,而且落叶比率明显高于龙王帽。自然干旱时杏的LOX活性表现为叶片升高,在根中变化不大。而且山杏叶片的LOX活性增加幅度比龙王帽大,峰值出现比龙王帽早。因此,干旱条件下抗旱的山杏叶片脂氧合酶活性比龙王帽提早增加而且叶片易早脱落。山杏叶片LOX活性急剧升高出现在叶片萎蔫衰老之前,推测LOX活性增强可能与引发衰老有关。     

UV-B radiation and photosynthetic irradiance acclimate eggplant for outdoor exposure

Treatment of greenhouse-grown eggplant (Solanum melongena L. var. esculentum Nees. 'Burpee's Black Beauty') seedlings with supplemental photosynthetically active radiation from cool-white fluorescent lamps increased growth of plants subsequently transferred outdoors relative to growth of plants that received no supplemental radiation or were shaded to 45% of solar irradiation in the greenhouse before transfer outdoors. Eggplant seedlings transferred outdoors were placed under plastic tarps either to provide relative protection from solar ultraviolet-B (UV-B) radiation (280-315 nm) using Mylar film or to allow exposure to UV-B using cellulose acetate. Protection of seedlings from UV-B radiation resulted in greater leaf expansion than for UV-B-exposed seedlings, but no change in leaf or shoot dry weight occurred after 9 days of treatment. Specific leaf weight increased in response to UV-B exposure outdoors. Exposure of eggplant to UV-B radiation from fluorescent sunlamps in the greenhouse also decreased leaf expansion and leaf and shoot dry weight gain after 5 days of treatment. However, there were no differences in leaf or shoot dry weight relative to control plants after 12 days of UV-B treatment, indicating that UV-B treated plants had acclimated to the treatment and actually had caught up with non-UV-B-irradiated plants in terms of growth.     

大田环境白及苗期生长和光合特性

以紫花三叉白及幼苗为试材,采用大田示范试验,基于前期育苗地幼苗长势评级分区情况,测定白及幼苗不同时期生长特性和倒苗期光合特性,通过主成分分析探究表征白及幼苗生长势的综合指标,以期为大田中培育白及壮苗提供参考依据。结果表明:大田环境下白及幼苗生长期株高、叶面积、地上部生物量、块茎生物量、新根生物量和地下部生物量在倒苗期较初苗期均有增长。倒苗期株高、叶面积、叶绿素含量、地上部生物量、老根生物量、新根生物量、块茎生物量、地下部生物量、暗呼吸速率(Rday)、最大净光合速率(Pnmax)、表观量子效率(AQY)均以小区B或A3(均为Ⅰ级苗)最大、小区D2或A1(均为Ⅲ级苗)最小,主成分分析得到表征生长的指标贡献率较高的为新根生物量、表观量子效率(AQY)、地下部生物量。     

苹果杂种树叶片在预选中的应用研究

作者研究了苹果杂种实生树果实与成年期叶片、成年期叶片与童年期叶片部分性状相关性,以解决早期选择问题.结果表明,苹果杂种实生树成年期叶片叶柄短与大果型、叶片面积大小与果实大小、叶形指数与果形指数之间存在着显著的正相关性;成年期叶片与童年期叶片在叶柄长度、叶片面积、叶形指数上又存在着极显著的正相关性.苹果育种工作者可以利用果实与叶片间的这些相关性,进行实生苗的早期选择和预先选择,淘汰不良的类型,减少供选杂种的数量,提高育种效率.     

生根粉对北五味子幼苗的影响

采用随机区组试验设计,用生根粉药剂对层积处理后经过催芽处理的北五味子种子进行浸泡处理,播种后对北五味子幼苗行测量调查。结果表明:经过生根粉药剂处理后的北五味子种子长出的幼苗在根、茎、叶等各项生理特征均优于CK,其中根长比CK增加了30.30%,侧根数目增加了50%,主根直径增加了22.5%,芽的数目平均增加了2.8个;幼苗植株叶绿素含量第5、6、7叶位比CK分别高19.22%、39.23%和19.07%,并且提前达到了一定的高度,进入有机物的积累时期,为第2年的良好生长提供了保证。     

冬春季节遮阴处理对香蕉假植苗生长的影响

冬季 (12～ 1月 )、春季 (3～ 4月 ) ,将从培养瓶中移出的香蕉组培苗置于大棚内 ,在 4种遮阴水平下进行假植炼苗 ,光照条件分别为 10 0 % (S10 0 ) ,33% (S33) ,10 % (S10 ) ,3 % (S3)。结果表明 ,不同光照强度下 ,香蕉苗的苗高、基径、叶长、叶宽、叶片数、叶面积、总根数和长根数都存在显著差异 ,但不同的性状对光照强度的反应不同。冬季有利于根系的生长 ,春季则更有利于地上部性状的生长。冬季和春季都以S33光照处理为最优 ,即适度遮阴有利于香蕉假植苗的生长发育。但春季各性状对遮阴水平适应的范围比冬季更宽 ,并且各性状在不同的季节对同一遮阴水平的反应也不相同 ,这表明光照强度与季节之间存在互作效应     

叶片切除对番茄扦插苗茎基部糖含量及不定根发生的影响

以番茄品种中杂302 为材料，采用幼苗叶片切除和茎基部水扦插的方法，研究叶片切除对番茄扦插苗茎基部糖含量和不定根发生的影响。结果表明：切除幼苗叶片处理，改变了番茄扦插苗茎基部糖代谢相关酶SUS、CWIN 的活性和相对表达量，显著降低了茎基部葡萄糖、果糖、蔗糖和可溶性总糖的积累水平（P ＜ 0.05），抑制了不定根发生。表明保留适当的叶片数对番茄扦插苗不定根发生有非常重要的促进作用。     

蚓粪复合基质对茄子幼苗生长的影响

以蚓粪复合基质和茄子幼苗为试材,研究蚓粪复合基质对茄子幼苗生长的影响。结果表明:在茄子整个幼苗生长期,蚓粪复合基质对茄子幼苗成苗率,地上部分的开展度、株高、茎粗、叶绿素、叶片数和鲜(干)重等增加作用显著优于对照基质。蚓粪中添加中低量氮素(0.5~1.0 kg尿素/m3)比高氮添加量(2.0 kg尿素/m3)更有利于茄子幼苗地上部分生长和鲜(干)重的累积。高氮添加量处理在中、后期的有益效果逐步显现。蚓粪复合基质幼苗的根长、根表面积、根体积和根尖数等在生长中、后期均显著高于对照基质处理;中低量氮素添加量有利于提高茄子幼苗成苗率,各处理成苗率在苗中、后期无明显变化。新鲜蚓粪与蛭石按4∶1的体积比混合后,添加适量无机养分制成的复合基质可以作为茄子育苗基质。综合成本和幼苗生长情况,蚓粪复合基质中以添加尿素1.0 kg/m3为宜。     

温度和辐射对一品红发育及主要品质指标的影响

 以辐热积(每日温度相对热效应×光合有效辐射, Photothermal p roduct, PTP) 为光温指标,通过不同扦插期的试验研究了温度和辐射与‘千禧’一品红发育和品质指标的定量关系, 明确了从短日至单苞期、单蕾期、多蕾期、开花期所需要的PTP。结果表明标准化株高净增量(株高净增量/扦插苗初始叶面积) 与PTP呈幂函数关系; 主干叶片净增数、侧枝叶片数、苞片数与PTP均呈线性关系; 冠高比与PTP呈负指数关系。     

短日处理诱导西双版纳黄瓜开花试验

西双版纳黄瓜是分布于我国西双版纳地区的一群独特的黄瓜资源,由于其光周期敏感的特点,育种应用较为困难。本试验采取8h/16h的短日照条件,研究了短日处理0、10、20、30、40d对西双版纳黄瓜开花的影响。结果表明,短日处理有显著的促雌效应,第1雌花节位提早,雌花数增多,并且随着短日处理天数的增加该效应愈强。检测分析表明短日处理诱导出的雌、雄配子均活力正常,可用于育种研究。     

一品红花色的探讨

对一品红、一品粉、一品白的苞片、叶柄和叶片的色素进行了测定。三者苞片和叶柄中的叶绿素含量无明显差异，但花色素的差异明显。短日照条件下，一品红叶片从上至下花色素含量递减，而叶绿素含量递。随短日照的时间持续，一品红苞片和定位叶片中花色素的成分不断增加，而叶绿素的成分不断。天竺葵色素是一品红中所含重要色素之一。